Weiland NHS, et al. - This study put forth a novel method for improved intraoperative non-invasive assessment of cerebral autoregulation (CA). This method involves amplification of spontaneous blood pressure (BP) fluctuations during surgery by imposing mechanical positive pressure ventilation at three different frequencies and quantifying CA from the resulting BP oscillations. Findings demonstrated that this novel method represented a reliable and non-invasive tool to quantify CA. Data also corroborated earlier evidence that CA is unaffected by sevoflurane anaesthesia.